2.3.2. Determination of total polyphenol content
The total phenolic content was determined using the Folin-
Ciocalteu method (Singleton, Joseph, & Rossi, 1965) with a few
modifications. One gram of dried Moringa leaf powder was
extracted into 80% methanol. A volume of 125 ml of the sample
solution and 125 ml of the Folin-Ciocalteu reagent was mixed and
vortexed for 1 min and allowed to stand for 5 min at room temperature.
1.75 ml of 5% Sodium carbonate in water was added and
allowed to react for 1.5 h at room temperature. The absorbance was
measured at 765 nm on a UVevisible spectrophotometer. Gallic
acid was used as the standard solution.
2.4. pH and instrumental color evaluation
For determination of the pH, 10 g of sample was homogenized
with 50 ml distilled water and the pH value was measured using a
digital pH-meter (HM-5S; TOA Electric Industrial Co. Ltd., Tokyo,
Japan). The effect of MOL on color properties (L*, a*and b*) of
cooked sausages was evaluated using a chroma meter (5104, No:
453, WPA Linton Cambridge UK).
2.5. Microbial analysis
Frozen samples were thawed to room temperature (28 C) and
10 g of each samplewas homogenized with 90 mL buffered peptone
and was properly blended.1 mL dilutions were inoculated onto TPC
petrifilm (PetrifilmR 3M) to obtain Total Plate Count and incubated
at 30 C for 48 h. Furthermore, 1 ml dilutions were inoculated on to
E coli petrifilm (3M™ Petrifilm E coli/Coliform count plates) and
Baired Parker medium (Oxoid, UK) to obtain E. coli and S. aureus
count respectively at 37 C for 24 h.
2.3.2. Determination of total polyphenol contentThe total phenolic content was determined using the Folin-Ciocalteu method (Singleton, Joseph, & Rossi, 1965) with a fewmodifications. One gram of dried Moringa leaf powder wasextracted into 80% methanol. A volume of 125 ml of the samplesolution and 125 ml of the Folin-Ciocalteu reagent was mixed andvortexed for 1 min and allowed to stand for 5 min at room temperature.1.75 ml of 5% Sodium carbonate in water was added andallowed to react for 1.5 h at room temperature. The absorbance wasmeasured at 765 nm on a UVevisible spectrophotometer. Gallicacid was used as the standard solution.2.4. pH and instrumental color evaluationFor determination of the pH, 10 g of sample was homogenizedwith 50 ml distilled water and the pH value was measured using adigital pH-meter (HM-5S; TOA Electric Industrial Co. Ltd., Tokyo,Japan). The effect of MOL on color properties (L*, a*and b*) ofcooked sausages was evaluated using a chroma meter (5104, No:453, WPA Linton Cambridge UK).2.5. Microbial analysisFrozen samples were thawed to room temperature (28 C) and10 g of each samplewas homogenized with 90 mL buffered peptoneand was properly blended.1 mL dilutions were inoculated onto TPCpetrifilm (PetrifilmR 3M) to obtain Total Plate Count and incubatedat 30 C for 48 h. Furthermore, 1 ml dilutions were inoculated on toE coli petrifilm (3M™ Petrifilm E coli/Coliform count plates) andBaired Parker medium (Oxoid, UK) to obtain E. coli and S. aureuscount respectively at 37 C for 24 h.
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